a) Field of the Invention
The invention is about an AC/DC converter for connection to a multi-phase AC network. Additionally it concerns a method relating to this technical area.
b) Background Art
AC/DC converters for connection to a multi-phase network are known. For example, U.S. Pat. No. 5,045,991 discloses such a converter which, with the aid of a six-pulse controlled bridge rectifier, rectifies a 3 phase AC current.
DE Patent 37 38 181 A1 discloses a similar arrangement in which a current rectifier has an output DC current which is controlled by a steady in phase switching of six bridge rectifier elements. The difference between the two patents is in the control logic where, especially in the first mentioned patent, the alternative current of the network remains approximately sinusoidal even under varying load.
U.S. Pat. No. 5,003,453 discloses an additional AC/DC converter with loading of the three phases of a 3 phase network. This converter feeds, in one version with all three phases and in another version with a single one of the three phases of the network, three parallel power factor correction circuits. These supply at their outputs DC current which is then changed again through a DC/DC converter for the various loads requested by a computer complex. The AC/DC converter is built multiply redundant and is able, during interruption of a network phase, or a power factor correction circuit, or a DC/DC converter, to deliver the current that is required by the computer. This AC/DC converter is quite complicated and is. especially built to deliver the diverse loads of a large scale computer, and the computer operation is not interrupted even when the converter needs to be worked on or repaired.